title: Identifying important life stages for monitoring and assessing risks from exposures to environmental contaminants: results of a World Health Organization review.
abstract: In this paper, we summarize exposure-related issues to consider in determining the most appropriate age ranges and life stages for risk assessment. We then propose a harmonized set of age bins for monitoring and assessing risks from exposures to chemicals for global use. The focus is on preconception through adolescence, though the approach should be applicable to additional life stages. A two-tiered set of early life age groups is recommended. The first tier involves the adoption of guidance similar to the childhood age groups recommended by the U.S. Environmental Protection Agency, whereas the second tier consolidates some of those age groups to reduce the burden of developing age-specific exposure factors for different regions. While there is no single "correct" means of choosing a common set of age groups to use internationally in assessing early life exposure and risk, use of a set of defined age groups is recommended to facilitate comparisons of potential exposures and risks around the globe, the collection of data and analyses of aggregate exposure and cumulative risk. Application of these age groups for robust assessment of exposure and risk for specific populations will require region-specific exposure factors as well as local environmental monitoring data.
authors.affiliation: National Center for Computational Toxicology, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA. Electronic address: Hubal.Elaine@epamail.epa.gov.
authors.forename: Elaine A
authors.initials: EA
authors.lastname: Cohen Hubal
authors.affiliation: Centre for Anthropological Research and Department of Anthropology and Development Studies, The University of Johannesburg, Auckland Park, South Africa. Electronic address: tdewet@uj.ac.za.
authors.forename: Thea
authors.initials: T
authors.lastname: de Wet
authors.affiliation: Centre for Rural Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. Electronic address: Lilo.Dutoit@wits.ac.za.
authors.forename: Lilo
authors.initials: L
authors.lastname: Du Toit
authors.affiliation: Regulatory Support & Science Policy Division, Office of Children's Health Protection (MC 1107T), Office of the Administrator, U.S. Environmental Protection Agency, Room 1130 EPA West Building, 1200 Pennsylvania Avenue, N.W., Washington, DC 20460, USA. Electronic address: Firestone.michael@epa.gov.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Firestone
authors.affiliation: Office of Research, Chulabhorn Research Institute, 54 Kamphaeng-phet 6 Road, Laksi, Bangkok 10210, Thailand. Electronic address: mathuros@cri.or.th.
authors.forename: Mathuros
authors.initials: M
authors.lastname: Ruchirawat
authors.affiliation: Center for Sustainability, Environment and Health, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands. Electronic address: jacqueline.van.engelen@rivm.nl.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: van Engelen
authors.affiliation: International Programme on Chemical Safety, World Health Organization, 20 Avenue Appia, CH-1211 Geneva 27, Switzerland. Electronic address: vickersc@who.int.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Vickers
mesh_terms: D000818:Animals; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000737:chemistry*; D004787:Environmental Pollution / Q000009:adverse effects*; D006801:Humans; D018570:Risk Assessment / Q000379:methods; D014481:United States; D014484:United States Environmental Protection Agency; D014944:World Health Organization
chemical_list: D004785:Environmental Pollutants
keywords: Childhood life stages; Cultural and geographic modifying factors; Developmental changes in children; Exposure assessment; Exposure factors; Exposure to environmental contaminants; Harmonized early life age groups; Risk assessment; Windows of exposure; Windows of susceptibility